Work on 1956 Viking begins

[electroking]

Hello,

This past week, I began working on my 1956 Viking (Eaton's store
brand, built by Electrohome) 21-inch set. I acquired it from an elderly
lady who claimed that the set had been retired to a corner of her
dining room in 1964, after her family bought a newer set. According
to her, the set had been working fine at the time.

So I removed the rear cover, and saw a lot of dust in a uniform thick layer
over every horizontal surface, no traces of burning or anything the like.
I removed the CRT socket, noting that the base on the tube was still
solidly glued in place. I tested the tube with a Heathkit tester, and
the needle was pegged to the max, as should be for a new tube according
to the manual. Cutoff checked OK as well.

After I put the CRT socket back in place, I studied my schematic, began
looking for electrolytic and other capacitors, and also proceeded to do
some professional work.

Earlier this evening, I felt an urge to do a smoke test, in spite of all the
warnings I have read here and elsewhere, especially in the case of a
set that has not been turned on in 44 years. With the rear cover still
off, I plugged the set, turned it on, and observed both sides. I had
rabbit ears installed, and a strong local channel tuned.

Fortunately, there were no clicks, pops or flames. I got clear sound with
no hum, but no picture at all. I just rotated the contrast and brightness
knobs, to no avail. The set was on for no more than 90 seconds I would
say. I checked that the CRT cathode was lit.

I suspect that there is no high voltage, and I am now afraid it could be
a dead flyback trans. Of course I don't intend to do any more live testing
until I have pulled the chassis and inspected underneath. Any ideas?

Also, this appears to be a 'one-piece' assembly, meaning that the CRT
is attached to the chassis rather than to the cabinet. Any advice on
pulling this? Thanks in advance.

P.S.: I thought it showed on the attached figure, but the CRT type
is 21ALP4A.

[marty59]

Without knowing any special notes from a Howard Sams, it should be simple! Remove all the knobs first and disconnect the speaker leads, and remove the chassis screws. Gently try to wiggle loose, then slide back...crt and all!
It's nice when it's all together, you can lay the whole thing on it's side to work on and do troubleshooting. Just make sure it's secure this way.

[bgadow]

I doubt it's the flyback. Probably a tube, cap or maybe a resistor.